Exosomes are lipid-encapsulated vesicles that are released by various cells into body fluids, including blood, urine, milk, saliva and cerebrospinal fluid. Fevrier B & Raposo G (2004) Current Opinion in Cell Biology 16, 415-421, Taylor D D, Gercel-Taylor C (2010) Gynecologic Oncology 116, 153-153, Pisitkun T, Shen R F, Knepper M A (2004) Proc Natl Acad Sci USA 101, 13368-13373, Miranda K C, Bond D T, McKee M, Skog J, Paunescu T G, Da Silva N, Brown D, Russo L M (2010) Kidney International 78, 191-199, Johansson S M, Admyre C, Rahman Q K, Filen J J, Lahesmaa R, Norman M, Neve E, Scheynius A Gabrielsson S (2006) Journal of Immunology 176, S184-S184, Sharma S, Rasool H I, Palanisamy V, Mathisen C, Schmidt M, Wong D T, Gimzewski J K (2010) ACS Nano 4, 1921-1926, Palanisamy V, Sharma S, Deshpande A, Zhou H, Gimzewski J, Wong D T (2010) Plos One 5(1): e8577. Exosomes contain various bio-molecules of their cell of origin, including proteins and RNA molecules. By remote communication via the harbored bio-molecules, exosomes regulate a variety of cellular pathways in recipient cells that relate to the progression and prognosis of disease conditions. Smalheiser N R (2007) Biology Direct 2:35, van Niel G, Porto-Carreiro I, Simoes S, Raposo G (2006) Journal of Biochemistry 140:13-21, Gibbings D J, Claudo C, Erhardt M, Voinnet O (2009) Nat Cell Biol 11: 1143-1149, Schorey J S, Bhatnagar S (2008) Traffic 9:871-881. Exosome research, based on detection of encapsulated biomarkers, has shown great potential in disease therapeutics and diagnostics. Rosell R, Wei J, Taron M (2009) Clinical Lung Cancer 10, 8-9.
Unfortunately, the vesicle structure of exosomes hinders the detection of exosome-harbored bio-molecules. The particular lipid composition of the vesicle and the presence of the harbored protein, nucleic acid, and other constituents confer protection to the vesicle against degradation and contribute to its stability in the extracellular environment. Schmid M, Jensen T H (2008) Trends in Biochemical Sciences 33:501-510; Houseley J, LaCava J, Tollervey D (2006) Nature Reviews Molecular Cell Biology 7:529-539.
A method for releasing the exosome encapsulated constituents for analysis is to apply lysis reagents. The lysis reaction time typically varies from several minutes to several hours and can compromise the integrity of the bio-molecules. Therefore, for translational and clinical applications, a need exists for rapid exosome-specific extraction and highly sensitive, specific detection of exosome associated bio-molecules. These and other needs are addressed by the methods and devices disclosed herein.